Litsinger, J.A. 1985. Integrated pest management for rice in Asia. p. 489-500. In: Proc. Conference on Women in Rice Farming Systems, September 26-30, 1983. IRRI, Philippines. 531 p. C19

As figure 29.2 from the previous page is unclear this figure shows more detail. The figure shows a record of rice leaffolder (Cnaphalocrocis medinalis) damage taken from 20 rice hills from 5 to 8 weeks after transplanting. The fields were selected from early planting to late planting as shown in the dates of transplanting. Two thresholds were evaluated, a high level at 30% damaged leaves and a lower level at 15% damaged leaves. Once the threshold value is exceeded the field is sprayed. This happened in the same two fields for both threshold levels as seen by the star in the histogram. The yield loss was then calculated from the high threshold level treatment (treatment 9 in figure 29.1) and in treatment 8 from the low threshold level. The yield was compared with the untreated as well as the yield in the complete insect control treatment (treatment 1) to determine if the pest control treatments were profitable.